Sandia Aerospace Granted Additional TSO on SAI 340 Quattro

Jan. 12, 2017 –The FAA has granted Sandia Aerospace an additional TSO on its popular SAI 340 Quattro Plus multifunction indicator. In addition to attitude, altitude, airspeed and slip, the SAI 340 is now TSO’d for Instantaneous Vertical Speed, or (I)VSI.

Unlike a standard VSI that has a six- to eight-second lag, the SAI 340 gives virtually immediate vertical speed indications. The vertical speed is shown on the SAI 340 in both a tape and digital format. In addition to the (I)VSI, the new software version also adds an adjustable altitude bug.

The SAI 340 is a stand-alone attitude indicator that is ideally suited for standby applications with today’s glass cockpits. It is also suitable as a stem gauge replacement unit in older aircraft.

The SAI 340 has an internal battery that provides two hours of standby operation in case of loss of aircraft power. The lithium-ion battery is enclosed in a metal case and meets the requirements of RTCA DO-347, ensuring safe operation.

With the addition of the (I)VSI TSO, the SAI 340 now holds eight separate TSOs. Existing SAI 340 owners can arrange to get their units upgraded to the latest software by contacting the Sandia Aerospace service department at or by phone at 505-341-2930.

Sandia Aerospace is providing the software at no charge to existing customers—they only pay for the labor to install the software, recalibrate the unit and shipping charges.

Check out the SAI 340 Quattro Plus and Sandia Aerospace’s other products at sandia.aero.